Back to results
US 4,302,308 AGranted
Method for electrolytic denitration of tobacco
AssigneePhilip Morris Incorporated
InventorGus D. Keritsis
Life of this patent
Estimating the term…
Loading patent…
Loading patent…
AssigneePhilip Morris Incorporated
InventorGus D. Keritsis
Estimating the term…
An improved process for denitrating tobacco with minimal losses of desirable tobacco solubles employing electrodialysis is disclosed. The process comprises subjecting an aqueous tobacco extract to membrane electrodialysis such that nitrate salts are extracted, without substantial loss of desirable tobacco solubles, while minimizing conflicting reactions in the electrodialysis unit and prolonging membrane life. Conflicting reactions are reduced and membrane life is enhanced by isolation of the electrodes to prevent electrolysis in the extract and brine by use of an anion permeable membrane adjacent the cathode and by use of a catholyte, the anion of which forms soluble salts with polyvalent cations. The denitrated extract when combined with denitrated insoluble fibrous tobacco materials may be employed to produce tobacco products having reduced nitrogen oxide delivery.
A method for denitrating aqueous tobacco extracts which comprises circulating an acidic tobacco extract having a solids content of about 5-50% and a resistivity of about 8-50 ohm-cm through the alternate cells of an electrodialysis unit having an anion permeable membrane toward the anode spaced no more than about 0.04 inches from an anion impermeable membrane toward the cathode, said membranes having a tightness sufficient to minimize transfer of nonelectrolyte substances, while circulating brine through the remaining cells and applying about 0.5 to 2.0 volts/cell pair to the unit, characterized in that the electrodes are isolated from all elements of the unit which are in direct electrolytic contact with the opposite electrode, the cell adjacent to the cathode has an anion permeable membrane toward the catholyte and an electrolyte the anion of which forms soluble salts with polyvalent cations is employed.
A method for denitration of tobacco which comprises:
Dependencies are inferred from the claim text.